With development of display technologies, three-dimensional (3D) technologies become a trend for future displays. Currently, there are two main switching methods for switching between 2D display mode and 3D display mode of existing 2D/3D stereo display devices. One switching method is mechanically moving a lens on a display panel to realize the 2D/3D switch. However, a device implementing such a mechanical type switch is large and cannot be easily controlled due to influences from vibrations, moisture, dust and the likes. The other switching method is utilizing a liquid crystal lens, which may have different refractive indexes for ordinary light (o light) and extraordinary light (e light), to change polarization direction of light as so to finally realize the 2D/3D switch. However, such a switch method has the following shortcomings of complicated device, high cost for the liquid crystal lens, narrow viewing angle, narrow operating temperature range of liquid crystal molecules, and the likes.